/*
 * Copyright (C) 2017-2019 Dremio Corporation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.dremio.exec.planner.logical;

import org.apache.calcite.plan.Convention;
import org.apache.calcite.plan.RelOptRule;
import org.apache.calcite.plan.RelOptRuleCall;
import org.apache.calcite.plan.RelTraitSet;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.core.Window;
import org.apache.calcite.rel.logical.LogicalWindow;

public class WindowRule extends RelOptRule {
  public static final RelOptRule INSTANCE = new WindowRule();

  private WindowRule() {
    super(RelOptHelper.some(LogicalWindow.class, Convention.NONE, RelOptHelper.any(RelNode.class)), "WindowRule");
  }

  @Override
  public void onMatch(RelOptRuleCall call) {
    final Window window = call.rel(0);
    final RelNode input = call.rel(1);
    final RelTraitSet traits = window.getTraitSet().plus(Rel.LOGICAL);
    final RelNode convertedInput = convert(input, traits.simplify());
    call.transformTo(
        WindowRel.create(
            window.getCluster(),
            traits,
            convertedInput,
            window.constants,
            window.getRowType(),
            window.groups));
  }
}
